The epidemiology of prurigo nodularis in Belgium

Prurigo nodularis (PN) is a rare, severely pruritic chronic skin disease, which seriously reduces patients' quality of life. PN prevalence in Belgium is unknown. To investigate PN prevalence, patient profile, diagnosis, and treatment strategies in Belgium. These insights will better support patient identification and treatments choice to address their specific needs. An anonymous questionnaire was sent to 800 dermatologists for data collection; 65 dermatologists (8%) completed the survey. Also, a search query in the electronic medical records system of a Belgian university hospital was performed. Based on this study, estimated PN prevalence in Belgium is in the range of 0.04-0.09%. PN was most common in women between the ages of 50 and 70 with multiple comorbidities, most importantly atopy and psychological/psychiatric comorbidities. However, few PN patients were treated by a psychologist/psychiatrist. PN is mainly managed with topical therapies (hydration, topical steroids, and calcineurin inhibitors). Of PN patients in Belgium, 61% are severely affected (IGA-CNPG score: 3-4) and received additional systemic treatment (at the time of the survey: antihistamines, methotrexate, cyclosporine, and gabapentin/pregabalin). Treatment of PN is often challenging due to chronicity and frequently associated comorbidities, which limit medical treatment options. In this context, screening for comorbidities, such as diabetes mellitus and kidney disease, is important for patient management. Also, the presence of psychological or psychiatric problems should be assessed, and if necessary, referred to specialized treatment. Education of other medical specialists (e.g. general practitioners, nephrologists or internal medicine/endocrinologists) can foster early identification and a more holistic approach to these multimorbid patients.